---

#define PR A0
#define BUZZER 10
#define LED 3

void setup() {
  pinMode(PR, INPUT);
  pinMode(BUZZER, OUTPUT);
  pinMode(LED, OUTPUT);
}

void loop() {
  int prValue = analogRead(PR);

  int frequency = map(prValue, 0, 1016, 200, 2000);

  tone(BUZZER, frequency);

  if (frequency >= 1500) {
    digitalWrite(LED, HIGH);
  } else {
    digitalWrite(LED, LOW);
  }

  delay(50);
}